The prior art includes sprinkler systems which can generate a variety of spray patterns. See for example U.S. Pat. Nos. 2,943,798 (Rienks) and 2,949,241 (Slonim).
A shortcoming of the prior art sprinkler systems is that while these systems can be used to generate different spray patterns, each spray pattern requires the purchase or production of a special corresponding baffle or plate. Such systems do not allow for easy adjustment of the spray pattern in the field. Another consequence of the prior art systems is that the spray patterns available tend to be limited to quarter spray, half spray and full spray.
The present invention overcomes this shortcoming of the aforementioned prior art by providing an arc adjustment plate which allows in the field adjustment of a sprinkler's spray pattern.
An advantage of the present invention is that adjustment of the sprinkler's spray pattern can be made in small angular increments. Another advantage is that by providing one universal spray unit, the need for specialized parts for different spray patterns is eliminated.
It is therefore a primary object of the present invention to provide an improved sprinkler head which includes means for in the field spray pattern adjustment.